Herpetic inflections are highly contagious skin eruptions or lesions, characterized by a cluster of small blisters or watery vesicles. The lesions are caused by an acute viral infection. The virus is from the genus Herpesvirus.
There are several types of viruses in the genus Herpesvirus. Two commonly known viruses are herpes types 1 and 2, referred to as HSV1 and HSV2. HSV1 causes orofacial lesions, commonly known as fever blisters or cold sores. These lesions most commonly appear on the lips, but may appear on the face, in the mucous membrane lining of the oral cavity, in the eye, and occasionally on the trunk or hands. Approximately 30% of the U.S. population suffers from recurrent episodes of HSV1. HSV2, which is less common than HSV1, causes genital lesions. Kirk & Othmer, Encyclopedia of Chemical Technology, Fourth Edition, Volume 3, Wiley-Interscience Publishers (1992), pp. 576-583.
Other types of Herpesvirus infections are caused by the varicella-zoster virus. The varicella-zoster virus causes varicella, commonly known as chicken pox, and herpes zoster, commonly known as shingles. Shingles affects the skin and nerves and is characterized by groups of small blisters or lesions appearing along certain nerve segments. The lesions are most often seen on the back and may be preceded by a dull ache in the affected site. Id.
There is no treatment known to kill the herpes virus. Therefore, the virus may remain in some latent form in the skin. Because there is no known treatment to kill the herpes virus or effectively prevent outbreaks of the lesions, recurrent herpes virus infections are common. Currently, the most commonly prescribed treatment of herpes virus infections is Zovirax.RTM. Ointment which contains the active ingredient acyclovir. Common over the counter treatments for herpes virus infections include Zilactin.RTM. Medicated Gel, Tanac.RTM. Medicated Gel, Orajel.RTM. Mouth-Aid, and Herpecin-L.RTM. Cold Sore Lip Balm. These treatments aid in helping to speed the healing of the lesions and the associated symptoms, but have not been shown to be efficacious in the treatment of herpes virus infections. Stannous fluoride has also been disclosed as a method for treating diseases having viral etiology. U.S. Pat. No. 5,098,716, issued Mar. 24, 1992, and International Publication No. WO 93/25211, published Dec. 23, 1993, to Embro disclose the use of stannous fluoride to treat herpes virus infections. However, the need still exists for new alternatives for treating herpes virus infections.
It has been discovered by the present invention that the topical administration of various stannous salts or stannous fluoride in combination with other stannous salts are effective for treating herpes infections and lesions. It has also been discovered that the topically-administered stannous salt compositions may also contain another therapeutic agent, such as an anesthetic, analgesic, or antibiotic. The topical application of these compositions will help to control the growth of the herpes virus, reduce the severity of the infection, and aid in reducing or eliminating the pain, redness, inflammation, and itching caused by the herpetic infections.
It is an object of the present invention to provide safe and effective methods for the treatment of herpes virus infections comprising the topical administration of various stannous salts or stannous fluoride in combination with other stannous salts. It is also an object of present invention to provide safe and effective methods and compositions which additionally contain another therapeutic agent. It is also an object of the present invention to provide a method comprising administering a stannous composition which helps to control the growth of the herpes virus, reduce the severity of the infection, and aid in reducing or eliminating the pain, redness, inflammation, and itching caused by the herpetic infections.
These and other objects of the present invention will become readily apparent from the detailed description which follows.
All percentages and ratios used herein are by weight of the total composition, and all measurements are made at 25.degree. C., unless otherwise specified.